[THREDDS #ZWT-786400]: Unable to open subsetted NetCDF files

Greetings,

I just tried to pull the data you described from that THREDDS server and I was 
able to plot accumulated precipitation in GrADS without issue.  I'm using 
version 2.2.1 that comes in apt on Ubuntu 22.04, and I tried to recreate your 
settings as best I could, as well as a few others just to see if I could break 
it.  Anything I tried seemed to work; see below for my GrADS output.  And while 
I'm not including them here, I was able to visualize that data as well.

What version of GrADS are you using?  Did you compile this from source or did 
you install it from a package manager like apt?

Would you be able to send me a full URL to a data set that breaks for you so I 
can try the same thing on my end?


My GrADS output:

Grid Analysis and Display System (GrADS) Version 2.2.1
Copyright (C) 1988-2018 by George Mason University
GrADS comes with ABSOLUTELY NO WARRANTY
See file COPYRIGHT for more information

Config: v2.2.1 little-endian readline grib2 netcdf hdf4-sds hdf5 
opendap-grids,stn geotiff shapefile
Issue 'q config' and 'q gxconfig' commands for more detailed configuration 
information
GX Package Initialization: Size = 11 8.5 
Running in Batch mode
ga-> sdfopen GFS_Global_0p25deg_20230220_1800.grib2.nc4 
Scanning self-describing file:  GFS_Global_0p25deg_20230220_1800.grib2.nc4
SDF file GFS_Global_0p25deg_20230220_1800.grib2.nc4 is open as file 1
LON set to 105 160 
LAT set to -47 -8 
LEV set to 0 0 
Time values set: 2023:2:20:19 2023:2:20:19 
E set to 1 1 

ga-> q file
File 1 : 
  Descriptor: GFS_Global_0p25deg_20230220_1800.grib2.nc4
  Binary: GFS_Global_0p25deg_20230220_1800.grib2.nc4
  Type = Gridded
  Xsize = 221  Ysize = 157  Zsize = 1  Tsize = 46  Esize = 1
  Number of Variables = 1
     total_precipita  0  t,y,x  Total precipitation (Mixed_intervals 
Accumulation) @ Ground or water surface

ga-> q config
Config: v2.2.1 little-endian readline grib2 netcdf hdf4-sds hdf5 
opendap-grids,stn geotiff shapefile
Grid Analysis and Display System (GrADS) Version 2.2.1
Copyright (C) 1988-2018 by George Mason University 
GrADS comes with ABSOLUTELY NO WARRANTY 
See file COPYRIGHT for more information 

This build of GrADS has the following features:
 -+- Byte order is LITTLE ENDIAN 
 -+- Athena Widget GUI DISABLED 
 -+- Command line editing ENABLED 
 -+- GRIB2 interface ENABLED  g2clib-1.6.3 
 -+- NetCDF interface ENABLED  netcdf-4.8.1 
 -+- OPeNDAP gridded data interface ENABLED
 -+- OPeNDAP station data interface ENABLED  libgadap 2.0 
 -+- HDF4 interface ENABLED  hdf-4.2r15 
 -+- HDF5 interface ENABLED  hdf5-1.10.7 
 -+- KML contour output ENABLED
 -+- GeoTIFF and KML/TIFF output ENABLED
 -+- Shapefile interface ENABLED


Best,
-Mike


> Hi,
> 
> Whenever I try to download subsetted NetCDF files from your NetCDF Subset
> Service for Grids webpage  (e.g.
> https://thredds-jumbo.unidata.ucar.edu/thredds/ncss/grid/grib/NCEP/GFS/Global_0p25deg/GFS_Global_0p25deg_20230220_1800.grib2/dataset.html
> ) and open it in GrADS, it always produces the following type of error:
> 
> 
> 
> 
> 
> *ga-> sdfopen GFS_Global_0p25deg_20230220_1800.grib2.nc
> <http://GFS_Global_0p25deg_20230220_1800.grib2.nc>Scanning self-describing
> file:  GFS_Global_0p25deg_20230220_1800.grib2.nc
> <http://GFS_Global_0p25deg_20230220_1800.grib2.nc>Error: nc_open failed to
> open file GFS_Global_0p25deg_20230220_1800.grib2.nc
> <http://GFS_Global_0p25deg_20230220_1800.grib2.nc>No such file or
> directorygadsdf: Couldn't ingest SDF metadata.*
> 
> This happens regardless of what combination of output format (netcdf3
> and netcfd4-classic) and CF compliance settings I use.
> 
> But for some strange reason, I can still open and plot the data in an
> application like Panoply.
> 
> Below is a screenshot of how I had the subsetting and output options set up
> during one of my attempts at downloading a file with accumulated
> precipitation for the Australian area:
> 
> [image: image.png]
> I'm just wondering why it's not working?
> 

Ticket Details
===================
Ticket ID: ZWT-786400
Department: Support THREDDS
Priority: Normal
Status: Open
===================
NOTE: All email exchanges with Unidata User Support are recorded in the Unidata 
inquiry tracking system and then made publicly available through the web.  If 
you do not want to have your interactions made available in this way, you must 
let us know in each email you send to us.